Safety ski binding

ABSTRACT

There is disclosed a hydraulically actuated gripping and release mechanism for a ski binding wherein a pair of hydraulic active cylinder-piston units are jointly connected in operative relationship with a spring backed reaction cylinder-piston unit. The first two of said cylinder-piston units are respectively responsive to lateral release forces and to vertical release forces and the reaction unit is connected for further coaction between the ski boot and the ski. Depending on the direction of movement of the ski boot with respect to the ski, one or both of the active cylinders are subjected to pressure which cause the transfer of hydraulic liquid therefrom into the reactive cylinder and depression of the piston therein against a resilient member. Flow inhibiting means are provided between the active cylinders and the reactive cylinder to minimize the transfer of liquid in response to momentary shocks but without appreciably inhibiting such transfer in response to a substantial or sustained force. By appropriate adjustment of the relationships between the cylinders, or of the spring means applicable to the one or the other thereof, any desired force relationship necessary for release can be predetermined between lateral or vertical falls or combinations thereof (diagonal falls). The system is applied in one embodiment to a binding for reception into the sole of a ski boot and in another embodiment is applied to a system external to the ski boot and engaging an end thereof.

Schweizer July 8, 1975 SAFETY SKI BINDING jointly connected in operative relationship with a [75] Inventor: Gottfried Schweizer, Vienna, spnng baciked 2 cyhnde.r'plston T first Austria two of said cyhn er-plston units are respective y responsive to lateral release forces and to vertical rei Asslgneei Gertsch AG, Zllg, Switzerland lease forces and the reaction unit is connected for fur- [22] Filed: Dec 26,1973 ther coaction between the ski boot and the ski. De-

pending on the direction of movement of the ski boot 1 pp ,499 with respect to the ski, one or both of the active cylinders are subjected to pressure which cause the transfer [30] Foreign Applicafion Priority Data of hydraulicliquid therefrom into the reactive cylinder D 29 [972 A and depression of the piston therein against a resilient usma 173/72 member. Flow inhibiting means are provided between the active cylinders and the reactive cylinder to mini- [ZIZ] 28255515350; mile the transfer of liquid in response to momentary i "5 T shocks but without appreciably inhibiting such trans- 1 0 can I fer in response to a substantial or sustained force. By appropriate adjustment of the relationships between [56] References cued the cylinders, or of the spring means applicable to the UNITED STATES PATENTS one or the other thereof, any desired force relation- 3,350,1l0 10/1967 Salomon 280/1135 T ship necessary for release can be predetermined be- Primary Examiner-Robert R. Song Attorney, Agent, or Firm-Woodhams, Blanchard and Flynn tween lateral or vertical falls or combinations thereof (diagonal falls). The system is applied in one embodiment to a binding for reception into the sole of a ski boot and in another embodiment is applied to a system external to the ski boot and engaging an end thereof.

10 Claims, 7 Drawing Figures PKTEHTEDJUL 8 ms SnEU 1. [5F 3 1 SAFETY SKI BINDING FIELD OF THE INVENTION The invention relates to a safety ski binding with an improved safety release, in which a damping and/or delay mechanism, such as a piston which displaces a liquid through a throttle opening, prevents the unintentional release of the binding and in which the liquid in turn moves a reaction piston which is under the pressure of an elastic element, such as a spring.

BACKGROUND OF THE INVENTION Safety ski bindings of the above-mentioned type are already known in various constructions. For example, French Pat. No. 1,517,557 describes a ski binding of the abovementioned type in which a cylindrical bore is provided in the jaw member, which bore is divided into two chambers by an orifice comprising a throttle. When a release occurs, the piston which is connected with the locking element urges the pressure fluid through this orifice or throttle. This causes a delay of the release operation and, where impacts occur for only a very short time, release of the boot does not follow.

German Offenlegungsschrift No. 1,578,974 provides a resistance means which acts against the disengaging movement of the support jaw or jaws, through which resistance means quick and short impacts are arrested with the result that disengagement occurs only during longer lasting forces acting in disengaging direction against a reduced resistance.

Finally a safety ski binding is known from Austrian Patent No. 292,580 which consists of a front and a rear jaw in which at least one jaw is provided with a sliding element which is itself constructed as a piston, or which is connected to a piston, which is movably guided in a cylinder and is loaded in one direction by a pressure fluid. in such case, the fluid pressure is created by a piston, which piston is guided in a cylinder and is under the influence of an elastic element such as a compression spring. In this known safety ski binding, the cylinder for the piston of the locking element is connected to the cylinder for the piston which is loaded by the elastic element through a channel or through a pressure line.

With the above-mentioned and similar safety ski bindings, a delayed disengagement or a replacement of mechanical means, like lever gearings, spring-loaded locks, etc. can be achieved. However, a further demand is made of present safety ski bindings, namely that the ski bindings be adjustable to the disengaging forces which are produced in various directions and which have various strengths. The various magnitudes of disengaging forces are presently determined by assuming the disengaging force produced in the horizontal plane to be one unit and by calculating the force produced in the vertical plane in relation thereto at a higher value, for example at twice the value. The lateral forces which lie between the horizontal and vertical plane result according to experience in a semi-ellipse and are identified as so-called diagonal forces. In order to allow for the release of these diagonal forces, in the mordem mechanical safety ski bindings correspondingly constructed control cams are provided.

However, the known hydraulic safety ski bindings cannot meet these demands because even in the lastmentioned safety ski binding, in which the cylinder for the piston of the locking element is connected to the cylinder for the piston which is loaded by the elastic element through a channel or a pressure line, a diagonal release cannot be accomplished.

The basic purpose of the invention is to further develop safety ski bindings of the last-mentioned type and to make such safety ski bindings also usable for the socalled diagonal release.

This purpose is attained according to the invention by providing at least three cylinders, of which two each receives one piston, which pistons receive the forces which lead to the release. and the third cylinder contains the known reaction piston.

The safety ski binding according to the invention attains this objective. A force which occurs in the horizontal plane operates only one cylinder and piston unit; and a force which occurs in the vertical plane operates both cylinders with their respective pistons. If now, as usually occurs in practice, there occurs a so-called diagonal load which lies between the horizontal and vertical planes, then the piston into the direction of which the resulting force acts is loaded more than the other one. For this reason the one piston is operated more and the other one less so that in the end the force which acts onto the reaction piston at a diagonal release is always smaller than at a release force lying in the vertical plane. Let us assume for example a release force in the horizontal direction 1 and in the vertical direction 2, then the resulting forces which extend between horizontal and vertical plane indicate values of between 1 and 2. In the case of the inventive construction the hy draulic mechanism can fully meet these requirements because the less than fully loaded piston always adds only a fraction of the value under 1 to the loaded piston.

One advantageous feature of the invention is that the release can take place even though a control cam is omitted. This for example is the case with a front jaw. However, in other embodiments of the invention, such as in so-called centerpoint bindings, the use of a presently known control cam is necessary. By using a control cam any desired release in horizontal or vertical, or in any desired direction lying therebetween, is possible.

A further advantageous feature of the invention consists in that the throttle opening between the cylinders is formed of nozzles which provide an additional throttling from the cylinders containing the force receiving pistons toward the cylinder containing the reaction piston. Thus, the liquid from the cylinder which directly receives the forces is throttled in the above-mentioned direction, while liquid flowing in the opposite direction passes easily. This makes it possible that during a return the liquid easily fills its original space and thereby permits the jaw also to return automatically and quickly into its original position.

According to a further characteristic of the invention the nozzle is constructed angularly at the inlet thereof but it is rounded off at the return point. According to a further feature of the invention this nozzle can also be constructed as an ejector in the direction of the release forces. It lies also within the scope of the invention to construct the nozzle wall in direction of the passage with an oppositely directed flow-preventing surface. All these embodiments serve to slow down the passage in direction of the release forces. It can also be easily conceived to realize the various braking possibilities in any desired combination.

BRIEF DESCRIPTION OF THE DRAWING Further embodiments of the invention will be described more in detail in connection with the drawings, in which:

FIGS. I to 4 illustrate one exemplary embodiment of the inventive safety ski binding, wherein FIGS. I and 2 or 3 and 4 illustrate in associated views the safety ski binding in a closed or in an open condition. FIG. I is a cross-sectional view along the line H of FIG. 2 and FIG. 2 is a cross-sectional view along the line III-Ill of FIG. 1; and FIGS. 3 and 4 correspond to FIGS. I and FIGS. 5 to 7 illustrate a different exemplary embodiment of the inventive safety ski binding, wherein FIG. 5 is a central cross-sectional view of FIG. 6 and FIG. 6 is a cross-sectional view along the line VIVI of FIG. 5 and FIG. 7 is the same cross-sectional view as FIG. 6, but in a so-called diagonal release position.

DETAILED DESCRIPTION The approximately U-shaped binding part 1 is arranged in a not illustrated ski boot and is secured in a conventional manner on the ski 7 by means of a housing 6 which carries the locking elements 3, 4 and 5. In the given exemplary embodiment the housing 6 is secured to the ski by means of screws 2.

The locking elements 3 or 4 and 5 load with their rearward ends a common elastic apparatus. This elastic apparatus is constructed in the exemplary embodiment as a hydraulic device which has three cylinders. The locking elements 4 and 5 are connected to pistons 8 and 9 which are sealed on the ends thereof which communicate with the hydraulic medium. Rubber rings 10 and 11 are used as seals. The locking element 3 is anchored in the housing 6 by means ofa pin 29. The reaction piston 13 is loaded by a spring 12 which in turn is supported by an abutment 22 on an eccentric cam 21. The reaction piston I3 is also sealed by a rubber ring 14 on its end opposite the pressure medium. The hydraulic device I5 itself consists substantially of three cylinders l6, l7 and 18 of which two are used to receive the pistons 8 or 9 and the third one 18 receives the reaction piston 13. The cylinders 16 and 18 and the cylinders 17 and 18 are connected respectively by openings 19 and 20. The openings 19 and 20, seen from the sides of the operating pistons 8 and 9, are constructed with entry corners and rounded-off continuations. Thus, during the operation of the locking elements 4 or 5 the pistons 8 or 9 receive an additional throttling through the hydraulic medium, however, during the return of the reaction piston 13 the return of the hydraulic medium occurs unprevented and immediately. As has already been mentioned, a spring I2 is connected between the locking element 3 and the reaction piston 13. This spring 12 is used as a locking spring in known mechanical safety ski bindings and can be adjusted between predetermined limits by means of an eccentric cam 21 which is secured on a screw 21.

The locking elements 3, 4 and 5 rest in locking pans 23, 24 or 25. The inclination of the locking pans 23, 24 or 25 in the lower and the lateral areas can be constructed in various ways. Thus advantageously the inclination 28 in the lower zone may be less than the inclination 26 or 27 in the lateral zone. This provides that during a release upwardly a larger release force must be overcome than during a lateral release. This known measure can, however, also be omitted from the inventive safety ski binding because by using the two forcetransmitting pistons and the spring-loaded reaction piston with the interpositioning of the hydraulic means IS a system has been created in which the release force which must be overcome is adjustable in horizontal, vertical or diagonal direction according to the conditions. Thus, during occurrence of an overload, at least one of the locking elements 3, 4 or 5 releases and the ski boot is set free. For the release and removal of the binding. a conventional release lever can be used. This release lever is not the subject matter of the invention and is therefore not described in detail.

The operation of the inventive safety ski binding can be clearly understood from FIGS. 3 and 4. Herein FIG. 3 illustrates a release in vertical direction and FIG. 4 a diagonal release. In the case of the load shown in FIG. 3, both locking elements 4 and 5 are operated against the inclination 28 in the lower area of the locking pan 24 or 25 (not shown). By moving the locking elements 4 and 5 the hydraulic liquid which is provided in the cylinders 16 and I7 is simultaneously and with the same force urged through the openings 19 and 20 against the spring force 12. In other words this adjustment has the consequence that a duplicate release force must be overcome than if for example an exclusively horizontal release occurs in which either only the locking element 4 or only the locking element 5 is to be adjusted.

In a so-called diagonal release, which lies between a horizontal and a vertical release, the locking elements 4 or 5 are each operated only partially. This means that, depending upon the respective angular position of the diagonal release, the one locking element is more active and the other locking element is less active. FIG. 4 shows that, for example, the locking element 5 was moved further backwardly and the locking element 4 was moved less backwardly in order to effect the necessary release.

A further exemplary embodiment is illustrated in FIGS. 5 to 7. The same parts are identified with the same reference numerals as in the exemplary embodiment according to FIGS. 1 to 4. Parts which in their effect and partially also in structure correspond to the already described parts, but are different in their construction, have been identified to indicate this difference with a prime symbol As can be seen from FIGS. 5 and 6, two bentleverlike sole holders 3], 32 are supported pivotally about the axes 33. Rollers 36 or 37 are supported on the outer sole holders 31 by means of substantially vertical axes 34 and 35, against which rollers the ski boot 38 which is indicated in dash-dotted lines is engaged.

The binding housing 6 or hydraulic means 15 are arranged on the ski 7 with the interpositioning of a support plate 39. Above this support plate two parallel arranged sliding members 40 which are adjustable in longitudinal direction are provided, the two ends 41, 42 of which sliding members are bent. The end of the sliding members which extends into the binding housing 6' is connected to an arm 44 of a clamp 45. Simultaneously the bent ends 43 of the sole holder arms 32 engage this flange portion 42 of the sliding member 40. The other ends of the sliding members 40 which are remote from the binding housing 6' are supported on the load pistons 8' or 9' which are connected to a spring-loaded reaction piston 13' through a hydraulic system 15'. The

remaining construction of the hydraulic system can be described similarly as in FIGS. 1 to 4. in this exemplary embodiment for the pre-tension of the spring 12' the position of the one piston 8' was constructed adjustably by means of a screw 43' in the associated cylinder I6. The sole holder 45 is pivotal about an axis 46 and is adjustable in height by means of a screw 47. Through this an adjustment to various thicknesses of boot soles is assured.

The operation of this exemplary embodiment is similar to that described in connection with FIGS. 1 to 4, with the exception that here no control cam is required. In the case of a horizontal release the bent portion 43 of one arm 32 of one or the other of the sole holders operates the corresponding one of the sliding members 40 through which only one of the pistons 8 or 9' is activated. in the case of a release upwardly by operating both arms 32 of the sole holders simultaneously, both sliding members 40 and thus both pistons 8' and 9' are operated simultaneously. This means that during a vertical release a force equal to twice the value of that corresponding to a horizontal release is required. In the case of a so-called diagonal release as already earlier mentioned the arms 32 of the two sole holders act depending on the position of the release, consequently a stress exists, the value of which lies between 1 and 2.

The invention is not limited to the described exemplary embodiments. Various possible combinations will be evident. For example, gas can be used as a hydraulic medium or also a liquid-gas composition can be used. By choosing the viscosity of the liquid which is used the delay can be accelerated or reduced. in using a gas or a gas mixture as a hydraulic medium, the response time can be adjusted in relation to various temperatures between predetermined limits. The use ofa liquid-gas system offers further possibilities for the acceleration or reduction of the response time.

Another possible modification consists in that the delay may be achieved by a special construction of the passage opening between the cylinders for the operating pistons and that for the reaction piston. For example, this may be accomplished by installing a corresponding control for a solely horizontal release and the cylinder of the unactivated piston may then serve as additional space for the partial receiving of the displaced hydraulic medium. However, attention must here be paid to the changing of the cylinder volume according to the spring force of the reaction piston. In this manner the relationship between horizontal and vertical release forces can be altered from the relationship 1 2. Moreover the force relationship which acts on the spring by means of the adjustment of the lever arms can also be carried out in a conventional manner. Furthermore by dividing the reaction piston and its cylinder a hydraulic system can be created in which also an asymmetrical stress by the two sole holders is possible. In this case both power pistons are made adjustable.

Although a particular preferred embodiment of the invention has been disclosed above for illustrative purposes, it will be understood that variations or modifications thereof which lie within the scope of the appended claims are fully contemplated.

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. In a safety ski binding for use in securing a ski boot to a ski having an improved safety release mechanism, in which a damping and/or delay mechanism compris ing piston means for effecting a displacement of a fluid through a throttle opening prevents the unintended release of the binding, whereby said fluid in turn moves a reaction piston which is under the pressure of a resilient means, the improvement comprising wherein said iston means comprises means defining at least three cylinders, two of said cylinders each having a piston therein adapted to receive the forces attempting to effect a release of said ski binding, said reaction piston being mounted in the third cylinder and being movable against the force of said resilient means in response to a displacement of fluid from one of said two cylinders into said third cylinder and external force receiving means engaging each of said two pistons and effecting an application of a force to each of said two pistons. one of said pistons engaged with said force receiving means being moved in response to a relative horizontal lateral movement between said one piston and said force receiving means, both of said pistons engaged with said force receiving means being simultaneously moved in response to a relative vertical movement between said pistons and said force receiving means, a simultaneous movement of both of said pistons requiring more force than a movement ofjust one of said pistons.

2. The improved safety ski binding according to claim 1, wherein said force receiving means engaging each of said pistons are conventional control cams.

3. The improved safety ski binding according to claim 1, wherein the throttle opening provided between the cylinders is formed of nozzles which provide an additional throttling from the cylinders containing the force receiving pistons toward the cylinder containing the reaction piston.

4. The improved safety ski binding according to claim 3, wherein the nozzle seen in direction of the pistons receiving the forces is constructed cornered at the inlet point, rounded off, however, at the return point.

5. The improved safety ski binding according to claim 3, wherein the nozzle in direction of the release forces is constructed as an ejector.

6. The improved safety ski binding according to claim 3, wherein the nozzle wall in direction of the passage is constructed with an oppositely directed, flowpreventing surface.

7. The improved safety ski binding according to claim I, wherein said resilient means is a spring and wherein the pre-tension of the spring for the reaction piston is variable by adjusting means for adjusting the initial position of an acting piston.

8. The improved safety ski binding according to claim 1, including means for adjusting the relationship between horizontal and vertical release force in the range of 1 2 3,5.

9. The improved safety ski binding according to claim 7, wherein said adjusting means is an adjusting screw.

10. The improved safety ski binding according to claim 1, wherein said force receiving means engaging each of said pistons are a pair of sliding members which are adjustable in longitudinal direction. 

1. In a safety ski binding for use in securing a ski boot to a ski having an improved safety release mechanism, in which a damping and/or delay mechanism comprising piston means for effecting a displacement of a fluid through a throttle opening prevents the unintended release of the binding, whereby said fluid in turn moves a reaction piston which is under the pressure of a resilient means, the improvement comprising wherein said iston means comprises means defining at least three cylinders, two of said cylinders each having a piston therein adapted to receive the forces attempting to effect a release of said ski binding, said reaction piston being mounted in the third cylinder and being movable against the force of said resilient means in response to a displacement of fluid from one of said two cylinders into said third cylinder and external force receiving means eNgaging each of said two pistons and effecting an application of a force to each of said two pistons, one of said pistons engaged with said force receiving means being moved in response to a relative horizontal lateral movement between said one piston and said force receiving means, both of said pistons engaged with said force receiving means being simultaneously moved in response to a relative vertical movement between said pistons and said force receiving means, a simultaneous movement of both of said pistons requiring more force than a movement of just one of said pistons.
 2. The improved safety ski binding according to claim 1, wherein said force receiving means engaging each of said pistons are conventional control cams.
 3. The improved safety ski binding according to claim 1, wherein the throttle opening provided between the cylinders is formed of nozzles which provide an additional throttling from the cylinders containing the force receiving pistons toward the cylinder containing the reaction piston.
 4. The improved safety ski binding according to claim 3, wherein the nozzle seen in direction of the pistons receiving the forces is constructed cornered at the inlet point, rounded off, however, at the return point.
 5. The improved safety ski binding according to claim 3, wherein the nozzle in direction of the release forces is constructed as an ejector.
 6. The improved safety ski binding according to claim 3, wherein the nozzle wall in direction of the passage is constructed with an oppositely directed, flow-preventing surface.
 7. The improved safety ski binding according to claim 1, wherein said resilient means is a spring and wherein the pre-tension of the spring for the reaction piston is variable by adjusting means for adjusting the initial position of an acting piston.
 8. The improved safety ski binding according to claim 1, including means for adjusting the relationship between horizontal and vertical release force in the range of 1 : 2 - 3,5.
 9. The improved safety ski binding according to claim 7, wherein said adjusting means is an adjusting screw.
 10. The improved safety ski binding according to claim 1, wherein said force receiving means engaging each of said pistons are a pair of sliding members which are adjustable in longitudinal direction. 